1. Field of the Invention
The present invention relates to a child-proof mechanism for a vehicle door latch device.
2. Prior Art
A prior art vehicle door latch device has a striker fixed to a vehicle body, a latch engageable with the striker, a ratchet engageable with the latch to keep the engagement between the latch and the striker, and an open lever connected to outside and inside open handles of a vehicle door to release the ratchet from the latch by opening actuation of the open handles.
Furthermore, the door latch device for rear doors mostly has a child-proof mechanism provided between the open lever and the inside open handle of the door. The child-proof mechanism is displaceable between a non-child-proof state of transmitting the opening actuation of the inside open handle to the open lever and a child-proof state of transmitting no opening actuation of the inside open handle to the open lever.
Furthermore, U.S. Pat. No. 5,520,425 and U.S. Pat. No. 5,618,068 disclose a powered closing mechanism which displaces the door to a full-closed position from an initially-closed position by moving the latch to a full-latched position from a half-latched position by using a motor power. The powered closing mechanism has a safety mechanism which is actuated in response to the rotation of the open lever. The safety mechanism urgently stops the actuation of the powered closing mechanism when the open lever is rotated by the opening actuation of the outside or inside open handle.
The prior art child-proof mechanism is uncongenial with the safety mechanism of the powered closing mechanism. That is, when the child-proof mechanism is in the child-proof state, the opening actuation of the inside open handle is not transmitted to the open lever, and therefore, it becomes impossible to actuate the safety mechanism by the opening actuation of the inside open handle.
Accordingly, it is an object of the present invention to provide an improved child-proof mechanism which is congenial with a safety mechanism of a powered closing mechanism.